Hydraulic transmission for machine tools



W45. M. A. MATHYS 2,368,259

HYDRAULIC TRANSMISSION FOR MACHINE TOOLS Filed Nov. 28, 1940 6 sheetssheet l J L I Wow/VJ Jan; 3@, 194s. M. A. MATHYS 2,3ss,259

HYDRAULIC TRANSMISSION FOR MACHINE TOOLS Filed Nov. 28, 1940 6Sheets-Sheet 2 cy S Wax O4 Wat figs why W Wow Jam. 30, N45. A, MATHYs2,368,259

HYDRAULIC TRANSMISSION FOR MACHINE TOOLS Filed Nov; 28, 1940 sSheets-Sheet 3 L H WU Qffax W Wa 2775s Jan 2%, i945. M. A. MATHYS2,368,259

HYDRAULIC TRANSMISSION FOR MACHINE TOOLS Filed Nev. 28, 1940 6Sheets-Sheet 4 I Q I B O O f3 a? J, Q

Jan. 30, 1945.

M. A. MATHYS Filed NOY. 28, 1940 6 Sheets-Sheet 5 Wax O4 Wol ya I Q9 GM,4%., 62? "W V rrowws Jan. 30', 1945.

M. A. MATHYS 2,368,259

HYDRAULIC TRANSMISSION FOR MACHINE TOOLS File d Nov. 28, 1940 6Sheets-Sheet .6

Patented Jan. 30, 1945 HYDRAULIC TRANSMISSION FOR MACHINE TOOLS Max A.Mathys, Detroit, Mich., assignor to Ex Cell- Corporation, Detroit,Mich., a corpora- .tion of Michigan Application November 28, 1940,Serial No. 367,523

14 Claims.

The present invention relates to improvements in machine tools, and hasparticular reference to a new and improved hydraulic transmission.

One of the primary objects of the present invention is to provide anovel hydraulic transmission for a reciprocable carriage which comprisesautomatic means for reversing the carriage, either with or without adwell at opposite ends of a predetermined range of movement, incombination with manual control mean for eflecting immediate reversal ofthe carriage at any intermediate point of movement.

Another object is to provide a new and improved hydraulic transmissionof the foregoing character including a mechanical interlock forrendering the manual control means functionally unavailable at oppositeends of the range of carriage reciprocation to effect movement beyondsaid range.

A further object is to provide a hydraulic transmission for areciprocable machine tool element including a novel pilot operated speedand direction control valve of simple and functionally efiicientconstruction.

Still another object is to provide a new and improved hydraulictransmission for a reversible machine tool element adapted for remotemanual control as for example to start or stop the operation, to varythe rate of movement, and to reverse the direction of movement.

Other objects and advantages will become apparent as the descriptionproceeds.

In the accompanying drawings,

Figure 1 is a view in perspective and on a reduced scale of a machineembodying the features of the invention.

Fig. 2 is a front elevational view on anenlarged scale of the machinecontrol mechanism.

Fig. 3 is a diagrammatic representation of the hydraulic system of themachine.

Fig. 4 is a plan view of a control panel forming part of the controlmechanism and shown separately of the machine.

Fig. 5 is'a side elevational view of the control panel.

Fig. 6 isa vertical sectional view through the control panel and takensubstantially along line 8-6 of Fig. 4.

Fig. 7 is a transverse vertical sectional view through the control paneltaken substantially along line 1-1 of Fig. 4.

Fig. 10 is a vertical sectional view taken substantially along line IlI-I 0 of Fig. 4.

Fig. 11 is a rear view of the machine on a reduced scale and showing theswitch control for the spindle drive.

Fig. 12 is a sectional detail view showing a carriage stop for useduring a dwell.

Referring more particularly to the drawings, the invention, for purposesof illustration, is disclosed as embodied ina machine tool comprising anelongated hollow base I on the top of which a carriage 2 is mounted forlongitudinal reciprocation. Two inverted generally U-shaped bridgemembers 3 are mounted respectively on opposite ends of the base I, andeach serves as a support for one or more, for example, three parallelspindle structures 4.

Suitable spindles 5 are joumaled respectively in the structures 4, andare adapted 'to be driven electrically, with the spindles at oppositeends ofthe machine under the control of a single-pole double-throwelectric switch 6 and limit switches 1 and 8. The switch 6 is adapted toclose and open the spindle drive circuits, including the limit switchesI and 8, on the rear of the machine base I (see Fig. 11), to start andstop the spindles alternately, and may be operated by any suitablemeans. In the present instance, the witch 6 has an actuating stem 9operatively connected to a piston I0 reciprocable in a stationaryhydraulic cylinder I2. Pressure fluid supply lines I4 and I5 I open toopposite ends of the cylinder I2, as shown diagrammatically in, Fig. 3.The limit switches 1 and 8 are normally open, and are adapted to beclosed alternately by a cam I 6 mounted on the carriage '2.

Each of the spindle 5 is provided with a brake I8, and the brakesfor'the two sets of spindles at opposite ends of the machine areconnected re-,

spectively for joint-actuation by two pistons I9 and '20 reciprocable instationary hydraulic c'ylinders 2| and 22. Opposite ends of thecylinders 2 land 22 are connected respectively to the pres- Fig. 8 is avertical sectional view taken substantially along line 88 of Fig. '7.

Fig. 9 is a vertical sectional view taken substantially along line 9-9of Fig. 2.

sure fluid supply lines I 4 and 15.} The arrangementis such that ifpressure fluid is supplied to the line I 4 and exhausted through theline IS, the

switch 6 will condition the drive circuits-for'the right end spindles l,and the brakes I8 for the same. spindles will be released. Upon movementof the carriage 2 past central position, the cam I6 will close theswitch 1 to complete the circuits for the -.right end spindles whichwill rotate. During this movement of the carriage, the drive circuitsfor the left end spindles 4 will be open at the switch 6 even though theswitch 8 remains and 23. In its preferred form, the operating mechanismcomprises a hydraulic carriag motor having a cylinder 23 mounted infixed position within the base I, and a piston 24 reciprocable in thecylinder and connected through a piston rod 23 to the carriage 2.Opening from the cylinder 23 respectively at opposite sides of thepiston 24 are .two fluid supply and discharge passages, conduits orlines 23 and 21 leading to a direction valve 23 (Figs. 3 and 8).

The direction valve may be of any desired construction, and preferablycomprises an elongated bore 23 defined by-a fixed sleeve in a valve body33. A valve piston 3| of the spool type, comprising axially spaced heads32, 33 and 34 separated by annular spaces 33 and 3,3, is mounted forreci-procation in the bore 23. Formed in longitudinally spaced relationalong and open to the periphery of the bore 23 are an annular groove orpressure port 31 connected to a pressure supply line 33, two annulargrooves or cylinder ports 33 and 43 at opposite sides of the port 31 andconnected respectively to (the-lines 23 and 21, two

annular grooves or feed exhaust ports 4| and 42 outwardly of theports'33 and 43 and connected to restricted exhaust lines 43 and 44, andtwo annular grooves or rapid traverse exhaust ports rapid traverse valv33 and a feed valve 34, operable by the carriage 2. The pilot controlalso includes two dwell mechanisms 33 and 33 which are available toprevent immediate institution of the rapid return at the ends of thefeed strokes in opposite directions. v

The various operating elements of the pilot control, together with themail control valve 23 43 and 43 outwardly of the port 4| and 42 and 3connected to an unrestricted exhaust line 41 leading to a sump 43.

The valve ports are so arranged that when the valve piston 3| is in theleft end position, both ports." and will be open-to the port 33, theport 43 will be open to the pressure port 31 and the ports 42 and 43will be closed from the space 33, thereby establishing rapid traverse ofthe carriage 2 to the left; when the piston is moved one step to theright, the port 4| will still be open to the port 33, but the port 43will be closed by the head'32, thereby establishing a feed movement tothe left; when the piston is located in the central position, as shown,the pressure port 31 will be closed by the head 33 and the port 45 and43- will be closed 'by the healds 32 and .34, thereby stopping thecarriage 2; when the piston is moved partially tothe right, the port 33will be opened to the pressure port 31, the porn; 43 will be opened tothe exhaust port 42, and the ports and 46 will be closed from the spaces35 and 33, thereby establishing a feed movement to the right; and whenthe piston is moved into the right end position, the port 43 will beopened to the port 43 to establish rapidtraverse to the right.

The pressure line 33 is adapted to be connected to any suitable sourceof pressure fluid,- such as a power driven pump 43 having an inrtakeline 33 opening from the sump 43. The available pressure from the pump43 i under the control of'a relief valve 3| adapted to by-pass excessfluid from the passage 33 to the sump.

The main valve 23 is a five position valve, and is operable by pilotcontrols comprising a plurality of pilot valves, namely, a start andstop cylinders 33 and 33 'in communication at their are incorporated ina unitary control panel 31 which is mounted on the front of the base I,and which is so arranged that the pilot valve 33 to 34 are operableselectively by suitable control dogs 33, 33, 13, 1| and 12 adiustablymounted in a T-slot 13 in the front side of the carriage 2. By selectionand adjustment of the dogs, and by adjustment of the rate of feed andthe selective use and adjustment of the dwellmechanisms 35 and 33,various machine cycles difleringin movement rates and seq nces may beobtained.

The pilot valves 33 to 34 comprise a plurality of vertical bores 3| to33 formed in and opening to the top of the panel 31, and a plurality ofspool valve plungers 33 to 33 reciprocable in the bores and projectingtherefrom through bushings 3| for selective actuation by the dogs 33 .to12. Pressure fluid from the passage 33 is directed through a branchedline or passage 32 to the respective valve bores 3| to 35, andactsagainst the upper piston areas of the spool plungers33 to 33, Aleakage drain line 33 opens from the upper end portion of each of thevalve bores 3| to 33 to the sump 43.

The start and stop valve 33 is available to effect adjustment of themain control valve 23 into neutral position. Thus, the valve bore 3| hasappropriately arranged port connections 34 and 35 with an exhaust line33 connected through the line 41 to the sump 43, and has an additionalport connection with a branched line 31 opening to slightly enlargedOpposite end portions of the main valve bore 23.l These portionsconstitute inner ends with the central portion of the valve bore 23 inwhich the valve member 3| is reciprocable. Two floating stop pistons I33and IN are slidable respectively in the inner ends oi the cylinders 33and 33 and are adapted for direct separable engagement with oppositeends of the -main spool valve 3|. Annular shoulders I32 and I33 limitinward movement 01' the pistons I33 and |3I so that when the latter areactuated by pressure fluid admitted through the line 31 they willconfine the spool valve 3| in intermediate stop position. The stoppistons I33 and MI are formed respectively with wide peripheral groovesI34 and I35 always in communication with the branches of the line 31,and with internal passages I33 and I31 opening from the grooves to theouter end faces of the pistons. When the stop plunger 33 is depressed(as shown in Fig. 3), the lines 32 and 31 are connected and hence thepistons I33 and IM are held against the shoulders I32 and I33 at theinner ends of the cylinders 33 and 33 to center the spool valve 3I. whenthe plunger the port 34 to the exhaust line 33 and the spool valve 33,direction control valves 3| and 32, a 13 valve 3I is released foractuation under the control of the direction pilot valves 3| and 32 ashereinafter described. I

The plunger 33 may' be operated manually from the front of the panel 31by means of a hand lever I33 to start and stopthe carriage 2, and isselfr-maintained in either position. When the plunger 33 is elevated tostart the operation,

in the lower end ofthe bore 8I supplied from the line 82 through abranch line I88.v .When the plunger 88 is depressed to stop theoperation, the line I88 is closed, and the lower end of the bore 8! isvented through a passage I III in the plunger and through the restrictedport connection 88 to the exhaust line 86.

The pilot valves 8| and 82 are operable respectively to institute theleft and right movements of the carriage 2, and to reset each otheralternatively for coaction with the dogs 88 and I8. Each has portconnections with the supply and exhaust lines 82 and 88, and with crosslines III and H2 opening respectively to the lower ends of the valvebores 83 and 82 and also to the inner ends of the cylinders 88 and 88.The port connections are so arranged that when the plunger 81 isdepressed, the line 82 will be connected to the line III, therebycausing upward movement of the plunger 88 to connect the line II2 to theexhaust line 86. As a result, the plunger 8'! is locked in depressedposition, the plunger 88 is held in its upward position, and thedirection valve 3| is shifted to the left to institute the carriagemovement to the left. Conversely, when the plunger 88 is depressed,pressure fluid is supplied through the line II2 to the lower end of thebore 82 to raise the plunger 81 and connect the line II I with theexhaust line 88. As a result of the attendant outward movement of theplunger 81, fluid is exhausted from the inner end of the cylinder 88 sothat the spool valve II is moved to the right to institute carriagemovement to the right.

The pilot valves 88 and 88 control each other and also the valve 28 forselective rapid traverse and feed. The feed positioiis of the main spoolvalve 28 are determined by feed limit pistons H3 and H4 reciprocable inthe outer ends of the cylinders 88 and 88 and limited in their inwardmovement by shoulders H5 and HE. A branched line Ill opens in parallelto the outer ends of the cylinders 88 and 88, and is adapted to beconnected by the feed control valve 84 either to the pressure line 82when the plunger 88 is depressed or to the exhaust line 88 when theplunger is fully elevated. Upon supply of pressure fluid to the line I",the feed pistons H3 and H4 are moved into their innermost position, asshown in Fig. 3, against whatever pressure may exist in the inner end ofone or the other of the cylinders 88 and 88, and serve through endabutment with the pistons I88 and IM t limit the range of movement ofthe valve member 3| so that the exhaust ports 45 and 48 will remainclosed during:

cross line H8 opening to the lower end of the bore 84. Hence, the rapidtraversejplunger 88 is elevated when the feed plunger 88 is depressed,

and thereupon relieves the line- 8 to loci; the latter in depressedposition. Likewise, the feed plunger 88 is moved into elevated positionwhen the plunger 88 is depressed, and thereupon relieves the line II8 tolock the latter plunger in depressed position. a

The feed, valve 84 also controls connection of.

the exhaust lines 43 and 44 to the drain'to obtain a pluralityofselective feeds in either direction of carriage movement. Thus, the borehas appropriate port connections with the lines 43 and 78 u, with mparallel lines m and m connected to the exhaust line 88, and with twoother parallel lines I22 and I23 also connected to the exhaust line.These port connections are so arranged that when the plunger 88 is fullyelevated, the lines 43 and 44 are blocked or closed; when the plunger ispartially depressed, the line 43 is connected to Suitable flowrestrictions, preferably adjustable orifice valves I24 to I21, areinterposed respectively in the parallel lines I28 to I23. Preferably,these orifice valves are alike in construction; each being independentlyadjustable from the front of the panel 81. The orifice valves controlthe escapement of motive fluid from the motor cylinder 23, and hencetheir adjustment determines the rate or rates of feed in eitherdirection of carriage travel. The two valves I24 and. I26 may beadjusted to obtain a fast feed and the two valves I28 and I21 may beadjusted to obtain a slow feed. Assuming the valves to be so adjusted,partial depression of the lunger 88 will institute a rapid feed and fulldepression of the plunger.

will institute a slow feed, in either direction of carriage movementdepending on which of the direction pilot valves SI and 82 is depressed.

To maintain the intermediate adjustment of the valve 84 for fast feed,the plunger 88 is rigid at the lower end with a hollow enlargement I28loosely movable in a chamber I 28 connected at the one end to the lineII8. Pressure fluid from the line II8 will pass along the enlargementtothe other or lower end of the chamber I28. Formed in enlargement I28 ia cylinder I38 open to an axial bore I3I in the plunger 88. A piston I32is reciprocable in the cylinder I38 and has an axial stem I33 adapted toproject through the lower end wall for engagement with the bottom wallof the cylinder I28. posed to thepressure in the chamber I28, and islimited in its outward movement by a snap ring I38 located in a grooveI38 in the wall of the cylinder I38. A coil compression spring I 34 inthe bore I3I tends to urge the piston I32 downwardly in the cylinderI30. The upper end of the bore I3I opens to a transverse bore I35adapted for connection, when the plunger 88 -is in intermediate orelevated position, with an annular groove I38 in the valve bushing 8Ialways in com munication with the pressure line 82, and for connectionwhen the plunger is fully depressed with the drain line 83. The upperend of the cylinder I38 is vented through a passage I31 in the pistonI32. to bore I3I, and the lower end is open to the cylinder I28.

'In operation,. when the plunger 88 is partially depressed into fastfeed position, as shown in Fig. 3, the opposite ends of the cylinder 128are exhausted. Fluid pressure acting on the upper end of thedifferential plunger 88 tends to urge the latter downwardly but alsoprojects the stem I33 to limit the downward movement. When the plunger88 is fully depressed, the upper end of the cylinder I38 is alsoexhausted, and thereupon the pressure acting on the upper end of theplunger serves to lock the latter in the slow feed position.

When the selectiv feed control plunger 88 is partially depressed intofast feedposition, the

pressure line 82 is connected with line II I for holding the feedpistons H3 and II4 intheir innermost positions, and through the line II8to lock the rapid traverse valve 53 in its upward The piston I32 is ex-'position. At the same time, the first feed control orifice valves I24and I28 are connected to control the passage of fluid out of the motor'23 through lines, 43 or 44. When the selective feed valve plunger 90 isfurther depressed to its slow feed position, the'connections remainunchanged except that the second feed orifice valves I25 and I21 areconnectedinto the lines 43 and 44. Upon depression of the rapid traverseplunger 09, the pressure line 82 is connected to line I I8 to lift theselective fe'ed plunger 80 to its uppermost position. Line III isthereby connected to exhaust line 88 to relieve the pressure onthe outerends of the feed pistons I I3 and I I4, allowing these pistons to moveto their outermost positions and permitting the valve piston 3| to movein the direction determined by the directional valves N or 82 to connectthe lines 28 or 21 directly with the sump through rapid traverse exhaustports 45 or 48. For any setting of the selective feed valve 84, thedirection of table travel will be, determined by the direction valves8i, and 82.. Thus, by proper setting of the machine controls, practicallany desired series of table movements is obtainable.

On occasion, it may be desirable to delay the reversal of the carriage 2at either end of the reciprocation, and the two dwell mechanisms 88 and88 are selectively available for this purpose.

Preferably, the dwell mechanisms are alike in construction so that adescription of one will sumce for both. The mechanism 85 comprises acylinder I38 in which a difl'erential spool piston I38 is reciprocablydisposed. One end of the cylinder of the diiferential areas of thepiston I38, both of which are now exposed to pressure, the piston I38will move progressively into its other end position. The time requiredfor this movement, which determines the length of the dwell period, iscontrolled by the setting of the orifice valve I40. At the end of thepiston movement, the exhaust groove I44 moves out of communication withthe line I42, and the latter is uncovered to communicate with the lineI4 I, thereby establishing the flow connection through the line I I2 tothe inner end of the bore 82. The direction plunger 81 is now elevatedand as a result it disconnects the line II I from the pressure line a:and connects it to the exhaust line 98 so as to establish the directionplunger 88 in depressed position. Since the line II2 is now connected topressure and the line III is connected to exhaust,

' the valve piston 3I will be shifted to the right to institute carriagemovement to the right.

The dwell mechanism" is identical except for the line connections, thevalve I43 in this instance being interposed in the cross line III. InFig. 3,

I38, facing the small area of the piston I33, is I constantly connectedthrough an adjustable restricted orifice valve I40 to the pressure line32. The other end of the cylinder I33, facing the large area of thepiston I 38, opens to a line I4I.

Another line I42 opens from an intermediate point in the cylinder I30,and is adapted to be uncovered by the piston I33, when the latter ismoved into one extreme position by the application of a difl'erentialpressure; A manually adjustable'two-position valve I43 in the line II2is available selectively to connect the dwell mechanism 85 operativelyinto the line H2, or to disconnect the mechanism when immediate carriagereversal is desired. In one position, the valve I43 leaves the line II2uninterrupted, and interconnects the lines I and I42. In the otherposition, the valve I43 serves in effect to interl pose the dwellmechanism 88 in the line ;II2 by connecting the pressure end to the lineI and the other end to the line I42. Formed in the periphery of thepiston I33 is an annular groove I44 connected through a passage I48 inthe piston to the exhaust line 88. In operation, fluid pressure from theline 02 passing through the control orifice I40 tends to locate thepiston I38 normally in its outer position in which communication betweenthe lines I and I42 is interrupted and in which the line I42 is open tothe exhaust groove I44. When the direction valve 62 is actuated tocondition the system for movement of the. carriage 2 to the right, theline H2 is connected to the pressure line- 82. If the valve I43 isadjusted'a's shown in Fig. 3 to conmeet the dwell mechanism 85, pressurefluid 'will now be supplied through the pressure end of the line IIZ,the valve I43 and the line I4I to the large end of the cylinder I30, andwill be blocked by the piston I30 from the other endof the line the'valve I43 for the dwell mechanism 88 is in the adjusted position toestablish a direct flow connection through the line I I I'and hence torender the dwell mechanism functionally inoperative. Both, valves I43are mounted in the control panel 8'I for adjustment from the front ofthe machine. Preferably, the valves I40 and I 43 for each dwellmechanism are connected for joint operation as illustrated in Fig. 9,the valve I43 when in position to connect the dwell mechanism permittinga predetermin'edrange of adjustment of the valve I40 without disturbingthe connections of the lines I and I42 with the interrupted portions ofthe line I IIv or II2. 1 --It will be understood that during a dwelloperation at either end of the carriage reciprocation, the carriage isheld positively against movement until reversal is effected. This may beeffected in any suitable manner; Preferably, as illustrated in Fig. 12,a stop screw I48! is adjustably threaded through the end flange oi thecarriage 2 and arranged for endwise abutment with a block I 48 rigidlysecured to the base I beneath the carriage. Similar positive stop meansis provided at both ends of the machine for coaction respectively withthe dwell mechanisms 88 and 88.

' One of the important features of the invention is to provide amanualcontrol whereby immediate reversal of the carriage 2 in either directionmay be effected when the dwell mechanisms 88 and 88 are conditioned foroperation in the automatic cycle. In the absence of such control, itwould be impossible to efifect immediate reversal of the carriage in theevent of anemer- 'gency,since the dwell mechanism would first havetooperate, and the table would continue to move during the dwell period.

"The manual control comprises a valve I48 hav- .mechanism 83 to. supplypressure fluid directly to the lower end of the plunger 88 and toexhaust the lower end of the plunger 81, thereby .pins I64 and I65extend reciprocably through instituting immediate movement of thecarriage to the left. This is accomplished byinterposing the valve I46in the cross lines III and H2, and by providing selective portconnections for. the end portions of these lines leading to the lowerends of the valvebores 63 and 62 respectively and reversibly-with thepressure and exhaust lines 92 and 96.

The valve I46 comprises a bore I41 formed in the panel 61, and areciprocatory valve plunger I48 in the bore. A manually operable controlknob I49 adjustable from-the front of the panel is operatively connectedto the valve plunger I46 to shift the latter selectively into any one ofits three positions of adjustment. The valve plunger I48 has twoperipheral grooves I56 and I5| adapted in the central position toconnect the port holes of the interrupted sections of the lines III andH2 so as to establish the normal flow passages therethrough. Also formedin the plunger I48 are two longitudinal slots I52 and I53 in constantcommunication respectively with the port holes of branches of thepressure and exhaust lines 92 and 96 opening to the bore I41.

The exhaust slot I53 is connected through a passage I54 in the plungerI48 to an exhaust port I55. The arrangement is such that upon upwardmovement of the valve plunger I46, the lines bores I66 and I61 in thepanel 61. The lower ends of the pins I64 and I65 are in engagement withthe upper edge of the lever I6| respectively at opposite ends. The upperends of the pins project from the panel 61 respectively adjacent theplungers- 61 and 66 for engagement by the reversing dogs 69 and 10 onthe carriage 2. In the present instance, the lower flat faces of thedirection dogs 69 and 16 are of such length that they will overlie thereset pins I64 and I65 respectively while actuating the direction valves6| and 62. Consequently, if the manual control valve I46 is in centralposition, the acting direction dog, when engaging the associateddirection valve, will prevent upward movement of the adjacent reset pinout of central position. The

other reset pin, however, is free to move upward- III and H2 will beinterrupted, and the portions thereof leading to the lower ends of thevalves 62 and 6| will be connected respectively to the pressure andexhaust lines 92 and 96. More particularly, the line 92 will beconnected through the slot I52 to the line III, and the line II2 will beconnected through the port I55, the 'pas sage I54 and the slot I53 tothe line 95. In the lower position of the valve plunger I46, theseconnections will be reversed, i. e., the line 92 will be connectedthrough the slot I52 to the line I I2, and the line I II will beconnected through the slot I53 to the line 95. The hand knob. I49 is soconnected to the plunger I48 that its position of adjustment to theright or left will indicate the corresponding direction of carriagetravel. More particularly, the hand knob I49 is secured on a shaft I56journaled in and extending through the front wall of the panel 61. Theinner end of the shaft I56 is rigid with a circular head I51 formed witha radial slot I56. A pin I59 mounted on the front of the valve plungerI49 and to the right side of the axis of the shaft I56 projects into theslot I56. Consequently, rotation of the knob I49 to the left in acounter- 1y so that the valve I46 may be actuated at any time to effectimmediate carriage reversal up to the point where automatic reversalwould occur and even during the dwell period. If the manual controlvalve I46 has been actuated out ,of central position, it is'allowed toremain in such position until automatic reversal is instituted, at whichtime the associatedreversing dog will depress the associated reset pinto return the valve into central position.

In operation, the machine will operate in accordance with its normalautomatic cycle as determined by the setting of the control dogs 66 to12 when the manual control valve I46 is in central position. Byapprdpriate adjustment of the valves I43, the automatic cycle may beconditioned for a dwell before reversal at either or both ends of thereciprocation, Adjustment of the valve 63 by its dog 1| will relieve thepressure acting on the outer ends of the feed pistons H3 and 4 toenlarge the range of reciprocation of the valve piston 3| so as toobtain rapid traverse. Actuation of the feed valve 64 by its dog 12 willreset the valve 63 for automatic actuation and will reestablish pressureagainst the outer ends of the pistons H3 and i|4 to limitadjustment ofthe main valve piston 3| to a feed range. In the partially depressedposition of the valve 64, the orifices I24 and I26. will be functionallyoperative to effect a fast rate of feed in either direction. In thefully depressed position of the valve 64, the orifices I25 and I21 willbe functionally operative to effect a, slow rate of feed in eitherdirecclockwise direction will elevate the plunger to institute movement01' the carriage 2 to the left and rotation to the right in a clockwisedirection to lower the plunger to institute movement of the carriage tothe right. A suitable'spring detent I66 is provided for normallymaintaining the valve plunger I46 in intermediate position. The

tion. Assuming that the carriage 2 is traveling to the right, actuationof the valve 6| by the dog 69 will reset the valve 62 and thereupon theline 'III willbe connected to pressure and the line 2 will be connectedto exhaust so as to shift the valve piston I3| to the left and therebyeffect plunger is adequately supported in its upper and lower positionsof adjustment by friction. Opposite ends of the bore I41 are normallyconnected to the exhaust line 66 to facilitate free adjustment of thevalve plunger I46. I A mechanical interlock is provided for preventingactuation of the manual control valve I46 out of central position in adirection to effect continued movement of the carriage beyond the limitsdefined by the direction control dogs 66 or 16. Referring to-Flg. 6,this mechanical interlock comprises a lever. |6| pivoted intermediateits ends at I62 in the panel and pivotally connected adjacent one end atI66 to the lower end of the valve plunger I46. Two vertical resetreversal of the carriage movement to the left.

with the dwell mechanism -66 functionally disconnected, as shown in Fig.3, this reversal will occifi' immediately. However, if the dwellmechanism' 66 is conditioned for operation, there will be a dwell periodbefore the valve 62 is reset to eil'ect-the carriage reversal. At theend of the movement to the left the valve 62 will be actuated to resetthe valve 6|, and thereupon the pressure and exhaustconnections to thelines III and 2 will be reversed so as to shift the valve piston 6| tothe right and thereby reinstitute movement of the carriage to the right.If the dwell mechanism 65 is conditioned for operation as shown in Fig.3, a dwell period will occur before the valve 6| is.

reset so as to delay automatic reversal. of the carriage. With ,thedwell mechanism 66 func-' tionally as shown in Fig. 3, this reversalwill occur immediately. However, if the dwell mechanism 68 isconditioned for operation, there will be a dwell period before the valve8| is reset to effect the carriage reversal.

At any time in the automatic cycle thus far described, the manualcontrol valve I48 may be actuated out of central position to effect animmediate reversal oi the carriage 2. For example, assuming that thecarriage 2 is moving to the left, the valve 62 will be up and-the valve8I will be down. Under these conditions, the manual control valve I48may be adjusted into its upper position without affecting the automaticcycle. The reset pin I65 will be projected upwardly alongside theplunger 88, but will be depressed by the dog 10 as an incident to theautomatic reversal to recenter the valve I48. However, it the valve I46is adjusted into its lower position, that portion or the line IIIopening to the lower end 1 of the bore 83 will be connected to exhaustinstead of pressure, and that portion or the line I I2 opening to thelower end of the bore 82 will beconnected to pressure instead of exhaustso that the two valves 8| and 82 will operate without do engagement toeflect immediate reversal of the carriage 2. This will project the resetpin I84 upwardly, but upon subsequent automatic reversal the pin will bedepressed by the dog 88 to recenter the valve I46.

Assuming that the carriage 2 has moved to the right and then to the leftpast the center position and is again moving to the right, uponengagement of the stop dog 88 with the valve 68, pressure fluid will bedirected through the line 81 to move the stop pistons I88 and INinwardly so as to center valve piston 8| and thereby automatically stopthe carriage.

The hydraulic transmission is well adapted for remote manual control. InFig. 3, remote controls are illustrated for starting, stopping andreversing the carriage 2, and for changing the rate of carriage'travel.

When remote control of the start and stop valve 68 is desired, a flowrestriction I66 is inserted in the branch pressure line I88, and acontrol line I61 is connected at one end to the lower end of the valvebore M. The other end of the line I61 is connected to a remote controlvalve I68. In the form shown, this valve comprises a rotary valve plugI68 having a hand lever I18 normally maintained in neutral position bycentering springs Hi to close the line I81. The plug I68is rotatable outof neutral position in opposite directions to connect the line I81respectively to the pressure line 82, thereby resulting in adjustment ofthe valve 68 to start the carriage operation, or to the exhaust line 86,

thereby resulting in adjustment of the valve 88 to stop the carriage.

When remote control of the rapid traverse and feed valves 68 and 64 isdesired, a flow restriction I12 is inserted in the line H8, and acontrol line I18 is connected to this line at a point between therestriction and the valve bore 84. The remote end of the control lineI18 is connected to a manual control valve I14 -similar tothe valve I88.

In neutral position, the valve I14 blocks the line I18. In one extremeposition, the valve I14 serves to connect the line I18 to the pressureline 82. Consequently, the valve plunger 88, it down,

aseaaoe It will be understood that during exhaust conditions, therestrictions I88 and I12 serve to permit lowering of the pressures inthe lower ends of the valve 'bores 8| and 84 respectively.

When remote control of the valve I 48 is desired, plugs I18 are insertedin branch exhaust lines I18 opening from opposite ends of the bore I41and normally connected to the leakage drain line 88. The lines I16 areconnected by a cross line I11. Interposed in the cross line I11 is aremote control valve I18 comprising a plug I18 with a hand lever I88normally maintained in central position by springs I8I. when in centralposition, the valve I18 opens the line I11 to the exhaust line 88 sothat the valve I48 may be freely adjusted by means of the control knobI48. Movement of the valve I18 out of central position reversibly inopposite directions will connect the opposite ends of the valve bore I41respectively and reversibly to the pressure andexhaust lines 82 and 86so as to effect selective adjustment of the valve I48 into its oppositeend positions. To disable the valve I18 when remote control is notdesired, the plugs I18 may be removed, and plugs I82, indicated indotted outline, may be inserted in opposite ends of the cross line I11.

I claim as my invention:

l. A hydraulic operating mechanism for a reversibly movable element oi!a machine tool comprising, in combination, a reversible hydraulic motorfor driving said element selectively in opposite directions, a source offluid under pressure, means including a reversible direction valve i'ordirecting fluid from said source alternately to opposite ends of saidmotor, pilot valve means operable respectively by said element uponmovement of the latter into opposite end positions for reversing saiddirection valve, in. dwell mechanism included in said first-mentionedmeans and operable upon actuation of said pilot valve means to delayreversal of said direction valve. and manual control means available atwill for efleoting immediate reversal of said direction valveindependently of said pilot valve means and of said dwell mechanism.

2. A hydraulic operating mechanism for a reversibly movable element of amachine tool comprising, in combination, a reversible hydraulic motorfor driving said element selectively in opposite directions, a source offluid under pressure, means including a reversible direction valve {ordirecting fluid from said source alternately to opposite ends or saidmotor; automatic pilot valve means operable by said element forcontrolling said direction valve, and manual pilot valve means forcontrolling said automatic pilot valve means independently of saidelement.

3. A hydraulic operating mechanism for a reversibly movable element of amachine tool comprising, in combination, a reversible hydraulic motorfor driving said element selectively in opposite directions, a source offluid under pressure, means including a reversible direction valve fordirecting fluid from said source alternately to opposite ends or saidmotor, automatic pilot valve meansoperable by said element to effectwill be elevated to institute feed operation. In

the other extreme position, the 'valve I14 serves to connect'the lineI18 to the exhaust line 88.

Consequently, the plunger 88, it .up, will be lowered to institute rapidtraverse operation.

reversal of said direction valve at opposite ends of movement or saidelement, and manual pilot valve means ror effecting reversal of saiddirection valve at an intermediate point within said rangeof movementindependently of said element; 3

4. A hydraulic operating mechanism for a reversibly' movable element ofa machine tool comprising, in combination, a reversible hydraulic motorfor driving said element selectively in opposite directions, a source offluid under presvalve means for controlling said automatic pilot valvemeans to effect selective reverse of said direction valve independentlyof said element.

5. A hydraulic operating mechanism for a reversibly movable element of amachine tool com- 7 prising, in combination, a reversible hydraulicmotor for driving said element selectively in opposite directions, asource of fluid under pressure, means including a reversible directionvalve for directing fluid from said source alternately to opposite endsof said motor, automatic pilot valve means operable by said element toeffect reversal of said direction valve at opposite ends of movement ofsaid element, manual pilot valve means for effecting reversal of saiddirection valve at an intermediate point within said range of movementindependently of said element, and remote control pilot valve means foroperating said manual pilot valve means.

6. A hydraulic operating mechanism for a re.-

' versibly movable element of a machine tool comprising, in combination,a reversible hydraulic motor for driving said element selectively inopposite directions, a source of fluid under pressure, means including areversible direction valve for directing fluid from said sourcealternately to opposite ends of said motor, automatic pilot valve meansoperable by said element to efiect reversal of said direction valve atopposite ends of movement of said element, manual pilot valve meansforefiecting reversal of said automatic pilot valve means independentlyof said element, and interlocked means for preventing said manrual pilotvalve means from eflecting continuation of said movement beyond saidopposite ends.

7. A hydraulic operating mechanism for areversibly movable element of amachine tool comprising, in combination, a reversible hydraulic motorfor driving said element selectively in opposite directions, a source offluid under pressure, means including a reversible direction valve fordirecting fluid from said source alternately to opposite ends ofsaidmotor, automatic pilot valve means operable by said element forcontrolling said direction valve, second pilot valve means having aneutral positionin which said automatic pilot valve means isfunctionallyoperative, and being adjustable out of neutral position intotwo diilerent positions selectively to eflect adjustment of saiddirection valve whereby to effect movement of said element in eitherdirection independently of control by said element.

8. A hydraulic operating mechanism for a reversible movable element of amachine tool comprising, in combination, a reversible hydraulic motorfor driving said element selectively in opposite directions, a source offluid under pressure,

means including a reversible direction valve for directing fluid fromsaid source alternately to opposite ends of said motor, automatic pilotvalve means operable by said element for controlling said directionvalve, second pilot valve means having a neutral position'in which saidautomatic pilot valve means is functionally operative,

being adjustable out of neutral position into two diflerent positionsselectively to eflect adJustment or said direction -valve whereby toeflect movement of said element in either direction independently ofcontrol by said element, andmeans for automatically insuring setting ofsaid-second pilot control means in said neutral position upon movementof said element to a predetermined position.

9. A hydraulic operating mechanism for areversibly movable element of amachine tool comprising, in combination, a reversible hydraulic motorfor driving said element selectively in opposite directions, a source offluid under pressure,

-means including a. reversible direction valve for directing fluid fromsaid source alternately to opposite ends of said motor, two pilot valvesoperable respectively to effect reversal of said direction valve inopposite directions, spaced dogs on said element alternately engagingsaid respective pilot valvesiupon movement of said element respectivelyintoy-opposite end limit positions, and secondary pilot valve meansselectively adjustable to effect reversalof said direction valves ineith direction within the range between said limit positionsindependently of actuation of said pilot valves by said dogs. 10. Ahydraulic operating mechanism for a reversibly movable element of amachine tool comprising, in combination, .a reversible hydraulic motorfor driving said element selectivelyin opposite directions, a source oi,fluid under pr ssure, means including a reversible direction valve fordirecting fluid from said source alternately to opposite ends of saidmotor, two pilot valves opof said direction valve andhaving anoperative. position for effecting movement of said elementin onedirection'independent of control of said pilot valves by said dogs, andmechanical interlock means operable by one of said dogs to return saidsecondarypilot valve means to neutral position at the end of said lastmentioned movement of said element.

11. A hydraulic operating mechanism for a reversibly movable element ofa machine tool comprising, in combination, a reversible hydraulic motorfor driving said element selectively-in-'op.v

posite directions, a source of fluid under pres-- sure, means includinga. reversible direction valve for directing fluid from said sourcealternately to opposite ends of said motor, two pilot valves operablerespectively to eflect reversal of said direction valve in oppositedirections, spaced dogs on said element alternately engaging saidrespective pilot valves upon movement of said element respectively intoopposite end limit positions, means operable upon actuation of one ofsaid pilot valves at one ofsaid limit positions to delay actu-v ation ofsaid direction valve for a predetermined dwell period with said elementconstrained against movement by .a flxed'stop, and secondary pilot valvemeans operable at willindependently of said last mentioned means foreflecting immediateactuation of said direction valve.

12. A hydraulic operating mechanism for a re versibly movable element ofa 11180111116170010021 prising, in combination, a reversible hydraulicmotor for driving said element selectively in on} posite directions, asource of fluid under pressure.. means including a'reversible directionvalve tor directing fluid from said. source to opposite ends 01' saidmotor, two pilot valves operable respectively to effect reversal of saiddirection valve in opposite directions, spaced dogs on said elementalternately engaging said respec tive pilot valves upon movement of saidelement respectively into opposite end limit positions,

means operable upon actuation of one of said pilot valves to delayactuation of said direction valve for a predetermined period, andsecondary pilot valve means operable to by-pass said last mentionedmeans and to eilfect immediate reversal of said direction valve.

13. A hydraulic operating mechanism for a reversibly movable element ofa machine tool comprising, in combination, a reversible hydraulic motorfor driving said element selectively in opposite directions,'a source offluid under pressure, means including a reversible direction valve fordirecting fluid from said source alternately to opposite ends of saidmotor, pilot valve means operable respectively by said element uponmovement of the latter into opposite end positions for controlling saiddirection valve and including two control lines adapted for alternateand interchangeable connection to said source and exhaust, hydrauliccontrol means available at will source and exhaust, and a manualactuator for said control means and being adjustable in the same generaldirection as the direction of movement of said element institutedthereby.

14. A hydraulic operating mechanism for a reversibly movable element ofa machine tool comprising, in combination, a reversible hydraulic motorfor driving said element selectively in opposite directions, a source offluid under pressure. means including a reversible direction valve fordirecting fluid from said source alternately to opposite ends of saidmotor, and for controlling the rate of movement of said element ineither direction, said valve comprising a bore, a reciprocatory valvemember in said bore having an intermediate neutral position, oppositeend i'eed positions within a limited range of adjustment, and oppositeend rapid traverse positions within a full range of adjustment,direction pilot valve means for directing fluid from said sourceselectively to opposite ends of said member to ell'ect reversal thereof,two cylinders opening respectively to opposite ends of said bore, twostop pistons in the inner ends of said cylinders and operable inwardlyinto limit positions to locate said member in'said neutral position,valve means for selectively directing fluid from said source to theouter ends of said pistons or relieving said pistons, two speed controlpistons in the outer ends of said cylinders and operable inwardly intolimit positions to act through said stop pistons to deflne said limitedrang outwardly to define said full range, and valve means forselectively directing fluid to the outer ends ofsald control pistons orrelievin said control pistons.

MAX A. MATHYB.

